1. Field
The present disclosure relates to a lighting apparatus, more particularly, to a lighting apparatus which can reflect light emitted from a light-emitting diode toward omnidirectional regions to radiate light broadly with a uniform light intensity and which can illuminate a light radiation region distant from a light source.
2. Background
Generally, the lighting industry has been under sustainable development and various studies on light sources, a light-emitting method, a driving method and lighting efficiency improvement have been made. A light source used in a lighting apparatus may be an incandescent lamp, an electric-discharge lamp, a fluorescent lamp or another appropriate type of light source based on various applications of the lighting apparatus such as for domestic usage, landscape usage, industrial usage, or the like.
The incandescent lamp which is a resistive light source has disadvantages due to relatively poor light-emitting efficiency and heat-radiation. The electric-discharge lamp have high costs and use a high voltage. The fluorescent lamp is harmful to the environmental as they use mercury.
To solve those disadvantages of such light sources, interest in light emitting diodes (LED) have been increasing because they have advantages in greater light emitting efficiency, and offer greater flexibility in structural as well as aesthetic designs. For example, LEDs may be configured to emit light in various colors.
Moreover, LEDs use a semiconductor element which emits light when a forward voltage is applied to the LED. Hence, LEDs may have a greater lifecycle as well as lower power consumption. In addition, LEDs have electrical, optical and physical properties which are amenable to mass production. Hence, the LEDs have been rapidly replacing the incandescent lamps and fluorescent lamps.
However, LEDs have a relatively small light radiation angle and lower light distribution characteristics. Hence, an area which can be illuminated by an LED light source may be relatively smaller. For example, when an LED type lighting apparatus having a small light radiation angle is installed on a ceiling, the lighting apparatus may be limited to illuminating relatively small areas located directly below the light source. Hence, the lighting apparatus may not be effective in use for illuminating a wide area and may fail to supply a sufficient intensity of illumination to relatively distant areas. As a result, a greater number of LED type lighting apparatuses may be required to maintain sufficient intensity to illuminate a wide area when compared to traditional type of lighting sources. Accordingly, installation costs may also increase.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.